She attends The Robert Napier School, a non-denominational mixed school, in Gillingham, Kent.

Her father, Danny Devine, 30, of Canterbury Street, Gillingham, told the Medway Messenger: "It's just political correctness gone absolutely mad. It's a harmless crucifix and she wears it as a symbol of her religion.

"I'm sure the school wouldn't dare ask anyone of another religion to remove a symbol representing their faiths or beliefs. This has upset the entire family."

He said: "The school has a policy of no jewellery to be worn by any students in years seven to 10. All parents and students are aware of this.

"In this particular instance, the student, and parent, were informed that the wearing of the chain was a health and safety hazard, but that we would allow a lapel badge to be worn.

"The only exception to our uniform rule we would consider making is if the jewellery were an essential requirement of a particular religion. We have no reason to believe this to be the case in this instance."

The debate has echoes of the row between British Airways and their employee Nadia Eweida, who fought for the right to wear a cross symbolising her Christian faith.

BA bans the wearing of jewellery, but has since announced it is to review its uniform policy to allow symbols of faith to be worn openly.